package com.jianggujin.redis.component;

import java.awt.event.ActionEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import javax.swing.Action;
import javax.swing.JTable;
import javax.swing.SwingUtilities;

public class TableCellListener implements PropertyChangeListener, Runnable {
    private JTable table;
    private Action action;

    private int row;
    private int column;
    private Object oldValue;
    private Object newValue;

    /**
     * Create a TableCellListener.
     *
     * @param table  the table to be monitored for data changes
     * @param action the Action to invoke when cell data is changed
     */
    private TableCellListener(JTable table, Action action) {
        this.table = table;
        this.action = action;
        this.table.addPropertyChangeListener(this);
    }

    /**
     * Create a TableCellListener with a copy of all the data relevant to the change
     * of data for a given cell.
     *
     * @param row      the row of the changed cell
     * @param column   the column of the changed cell
     * @param oldValue the old data of the changed cell
     * @param newValue the new data of the changed cell
     */
    private TableCellListener(JTable table, int row, int column, Object oldValue, Object newValue) {
        this.table = table;
        this.row = row;
        this.column = column;
        this.oldValue = oldValue;
        this.newValue = newValue;
    }

    /**
     * Get the column that was last edited
     *
     * @return the column that was edited
     */
    public int getColumn() {
        return column;
    }

    /**
     * Get the new value in the cell
     *
     * @return the new value in the cell
     */
    public Object getNewValue() {
        return newValue;
    }

    /**
     * Get the old value of the cell
     *
     * @return the old value of the cell
     */
    public Object getOldValue() {
        return oldValue;
    }

    /**
     * Get the row that was last edited
     *
     * @return the row that was edited
     */
    public int getRow() {
        return row;
    }

    /**
     * Get the table of the cell that was changed
     *
     * @return the table of the cell that was changed
     */
    public JTable getTable() {
        return table;
    }

//
//  Implement the PropertyChangeListener interface
//
    @Override
    public void propertyChange(PropertyChangeEvent e) {
        // A cell has started/stopped editing

        if ("tableCellEditor".equals(e.getPropertyName())) {
            if (table.isEditing())
                processEditingStarted();
            else
                processEditingStopped();
        }
    }

    /*
     * Save information of the cell about to be edited
     */
    private void processEditingStarted() {
        // The invokeLater is necessary because the editing row and editing
        // column of the table have not been set when the "tableCellEditor"
        // PropertyChangeEvent is fired.
        // This results in the "run" method being invoked

        SwingUtilities.invokeLater(this);
    }

    /*
     * See above.
     */
    @Override
    public void run() {
        row = table.convertRowIndexToModel(table.getEditingRow());
        column = table.convertColumnIndexToModel(table.getEditingColumn());
        oldValue = table.getModel().getValueAt(row, column);
        newValue = null;
    }

    /*
     * Update the Cell history when necessary
     */
    private void processEditingStopped() {
        newValue = table.getModel().getValueAt(row, column);

        // The data has changed, invoke the supplied Action

        if (!newValue.equals(oldValue)) {
            // Make a copy of the data in case another cell starts editing
            // while processing this change

            TableCellListener tcl = new TableCellListener(getTable(), getRow(), getColumn(), getOldValue(),
                    getNewValue());

            ActionEvent event = new ActionEvent(tcl, ActionEvent.ACTION_PERFORMED, "");
            action.actionPerformed(event);
        }
    }

    public static TableCellListener addTableCellListener(JTable table, Action action) {
        return new TableCellListener(table, action);
    }
}